open-witness

open witnesses

https://github.com/AshleyYakeley/open-witness

Version on this page:	0.4.0.1
LTS Haskell 24.18:	0.7
Stackage Nightly 2025-11-04:	0.7
Latest on Hackage:	0.7

See all snapshots open-witness appears in

BSD-3-Clause licensed and maintained by Ashley Yakeley

This version can be pinned in stack with:open-witness-0.4.0.1@sha256:da0e1c622b5e72825bda84d76565709710e4b01eb63af56d2a1d7f8cfb1f1386,2176

Module documentation for 0.4.0.1

Data
- Data.OpenWitness
- Data.Type
  - Data.Type.Heterogeneous

Depends on 7 packages(full list with versions):

base, constraints, hashable, random, template-haskell, transformers, witness

Open witnesses are witnesses that can witness to any type. However, they cannot be constructed, they can only be generated in the IO monad. See the paper Witnesses and Open Witnesses (http://semantic.org/stuff/Open-Witnesses.pdf).